Do you put grease (or anything) on bolts before tightening back into block/manifold?

[WIBoater]

After engine block and manifold drainage (winterization) do you put grease (or anything) on bolts before tightening back into block and manifold?

Those bolts were a pain to unscrew for drainage. Previous owner must have been "Superman"!

[MN Ryan]

Seems like some anti-seize compound would be beneficial, but I am no expert.

[Scooter G]

This sure to be a "what oil do I use thread".

I use Permatex Anti-Seize on most erverything that doesn't require loctite, especially anything engine block related.
40 years of success stories. Bolts will hold their torque, and come loose when needed.
It is the gift that keeps giving though, one little misplacement, and is like glitter, it goes everywhere, lol.

[MN Ryan]

LOL, 100% truth on the glitter comment!

[WIBoater]

Thank you for replies!
Someone else just recommended "plumbers putty".

[MN Ryan]

Plumber's putty? Uh, I would not try that.

This is what you want: https://www.permatex.com/products/lu...ubricant-8-oz/

[Jonny Quest]

Proceed with caution here! Lubricant (anti-seize) on threads can change the torque specs.

from EngineeringToolbox.com

When a bolt is lubricated - less torque is required to achieve bolt axial load or tension. Reduction of torques for lubricated vs. dry bolts are indicated in the table below.

Torque Reduction % based on Lubricant:

Graphite = 50-55%
White Grease = 35-45%
SAE 30 Oil = 35-45%
No Lube = 0%

My understanding is that Anti-Sieze is 25-30% reduction in torque.

JQ

[Scooter G]

Possibly, maybe, probably a reduction in torque. Logic would tend to think the opposite, but I won't argue with science. Thanks for the input Jonny Quest, good stuff.

When you find something that seems to work, whether reality or snake oil, you tend to keep going with it. I had someone suggest it when I had this older than time Ford pickup that would just decide to spin the lug nuts off going down the road, no matter how many times a week I tightened them, super fun. I know there were other extenuating factors involved, but when you are only making $12 bucks an hour, A-S solved the problem. Then we started using it on our race cars, never lost a head gasket, rocker arm, or intake manifold leak, and you could actually remove header bolts without learning new cuss words.

If you really want to have some fun, put some under your buddy's truck door handle, see how long that friendship lasts, or be prepared for the retaliation comeback, lol.

[bturner]

I've been lectured on Jonny's statement from a couple of my more skilled mechanic friends, then was told I was a hack mechanic over beers later (Guy friends having beers after a day working on cars/boats can be so cruel). My response was that there are no meaningful torque specs for a drain plug or knock sensor that would be significantly affected by my putting sealant or anti-seize on them. The point being it's a drain plug not a crank shaft main bolt on a drag car. Jonny is right but in the context of drain plugs IMO it really doesn't apply.

I started using this Permatex thread sealant a couple years back for gas lines, pipe threads and such. It's not like Loc Tite which is more like a glue. It really worked good on the fill screws for the oil bath hubs.

https://www.permatex.com/products/th...sealant-50-ml/